Scott Menzie asks: > > Does anyone out there know a good way to quench rhodamine. Ive got a > researcher doing phagocytosis assays and needs to quench rhodamine > labeled beads which have not been phagocytized. Does trypan blue work? > If it does or anything else does what concentration do you recommend? > Thanks in advance for your help!! > For any quencher to work, the beads would have to be labeled only on the surface. The "rhodamine" beads from polysciences, and many other fluorescent beads, are impregnated with dye, which, being in the polymer matrix, is not accessible to a water-soluble quencher like trypan blue, and it would probably not be easy to find an hydrophobic quencher which would get into the beads from an aqueous solution. That's why a lot of people who do phagocytosis assays work with bacteria surface labeled by incubation with FITC, etc.; the fluorescence of these particles can be quenched. -Howard
This archive was generated by hypermail 2b29 : Wed Apr 03 2002 - 11:52:58 EST